grpc: add caller info to client and wrap innerClient (#8704)

ref #8593

Signed-off-by: okJiang <[email protected]>

Co-authored-by: ti-chi-bot[bot] <108142056+ti-chi-bot[bot]@users.noreply.github.com>

Author: okJiang

Diff for: client/caller/caller.go

@@ -0,0 +1,67 @@
+// Copyright 2024 TiKV Project Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//	http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package caller
+
+import (
+	"os"
+	"path/filepath"
+	"runtime"
+	"strings"
+)
+
+type (
+	// Caller ID can be understood as a binary file; it is a process.
+	ID string
+	// Caller component refers to the components within the process.
+	Component string
+)
+
+const (
+	// TestID is used for test.
+	TestID ID = "test"
+	// TestComponent is used for test.
+	TestComponent Component = "test"
+)
+
+var processName ID
+
+func init() {
+	processName = ID(filepath.Base(os.Args[0]))
+}
+
+// GetCallerID returns the name of the currently running process
+func GetCallerID() ID {
+	return processName
+}
+
+// GetComponent returns the package path of the calling function
+// The argument upperLayer specifies the number of stack frames to ascend.
+// NOTE: This function is time-consuming and please do not use it in high qps scenarios.
+func GetComponent(upperLayer int) Component {
+	// Get the program counter for the calling function
+	pc, _, _, ok := runtime.Caller(upperLayer + 1)
+	if !ok {
+		return "unknown"
+	}
+
+	// Retrieve the full function name, including the package path
+	fullFuncName := runtime.FuncForPC(pc).Name()
+
+	// Separates the package and function
+	lastSlash := strings.LastIndex(fullFuncName, ".")
+
+	// Extract the package name
+	return Component(fullFuncName[:lastSlash])
+}

Diff for: client/caller/caller_test.go

@@ -0,0 +1,36 @@
+// Copyright 2024 TiKV Project Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package caller
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestGetComponent(t *testing.T) {
+	re := require.New(t)
+
+	re.Equal(Component("github.com/tikv/pd/client/caller"), GetComponent(0))
+	re.Equal(Component("testing"), GetComponent(1))
+	re.Equal(Component("runtime"), GetComponent(2))
+	re.Equal(Component("unknown"), GetComponent(3))
+}
+
+func TestGetCallerID(t *testing.T) {
+	re := require.New(t)
+
+	re.Equal(ID("caller.test"), GetCallerID())
+}